In the following descriptions, radian is used as a unit for phases. An interferometric technique using interference of light, particularly digital holography, is one of recently attractive measurement methods because of its feature of enabling three-dimensional information of an object to be obtained in a noncontact and nondestructive manner.
Digital holography is a technology in which an image of a three-dimensional object is reconstructed by use of a computer on the basis of interference fringes obtained by irradiation of the three-dimensional object with light. Generally, for example, interference fringes formed by (i) object light obtained by irradiation of a three-dimensional object with light and (ii) reference light which is coherent with respect to the object light are recorded by use of an image capturing element such as a CCD (charge coupled device) or a CMOS (complementary metal oxide semiconductor). The image of the three-dimensional object is reconstructed by a computer on the basis of the recorded interference fringes.
Patent Literature 1 discloses a technique of performing a measurement and recording step of sequentially and separately measuring and recording an interferometer signal obtained by digital holography and a fluorescence signal from a sample and a step of combining the interferometer signal and the fluorescence signal in order to reconfigure the three-dimensional image.
Patent Literature 2 discloses a technique of optically detecting fluorescence from an object.
Patent Literature 3 discloses a technique of measuring a polarized light component of fluorescence emitted by a sample.
Patent Literatures 4 to 7 each disclose a technique employing fluorescence detection.